The Marna Bug is an enemy in Grandia. It can be found on Marna Road and is one of the first enemies Justin and Sue encounter within the game. Marna Bugs may appear alongside Giant Centipedes and have the ability to cast String Orb.
As the Marna Bug is one of the first enemies in this game, there really is no strategy needed to defeat it. By simply using normal attacks, Justin's V-Slash or Sue's Puffy Kick, these enemies can be disposed of quickly.